[flexcoders] addChild using actionscript

[ew6014]

hi guys. i was reading flex3 for dummies page 221 on containers and it gave an 
example of adding childen using actionscript. it worked fine. but i thought 
about adding a removeChild function. but it doesnt seem to be working. can 
someone tell me why?

i apologize if this is a stupid mistake.

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<?xml version='1.0' encoding='utf-8'?>
<mx:Application xmlns:mx='http://www.adobe.com/2006/mxml' layout='vertical'>
<mx:Script>
        <![CDATA[
                
        import mx.controls.CheckBox;
        private function addCheckBox():void 
        {
        var checkBox:CheckBox = new CheckBox();
        checkBox.label = "Checkbox " + (myVBox.numChildren + 1);
        myVBox.addChild(checkBox);
        }

        private function removeCheckBox():void 
        {
        var checkBox1:CheckBox = new CheckBox();
        checkBox1.label = "Checkbox " + (myVBox.numChildren - 1);
        myVBox.removeChild(checkBox1);
        }
        ]]>
</mx:Script>
<mx:Button label='Add Checkbox' click='addCheckBox()' />
<mx:Button label='Remove Checkbox' click='removeCheckBox()' />

<mx:VBox id='myVBox' />
</mx:Application>